Datasheet
LT3518
15
3518fe
TYPICAL APPLICATIONS
1000:1 PWM Dimming at 120Hz Effi ciency
Buck Mode 1A LED Driver with Open LED Protection and Sync Input
1A
LED1
LED6
D1
C3
10µF
R1
49.9k
R2
2.00k
FB
R3
5.62k
L1
10µH
FB
C2
2.2µF
C4
0.1µF
R
SENSE
100m
M1
C1
2.2µF
V
REF
ISP
TGEN GNDV
REF
VC
R
T
16.9k
1MHz
3518 TA05a
C5
0.1µF
V
IN
SHDN
CTRL
PWM
SYNC
FB
SS
RT
SW
PV
IN
32V
V
IN
3.3V
ISN
LT3518
TG
PWM
SYNC
3.3V, 1.2MHz
C1: KEMET C0806C225K4RAC
C2: MURATA GRM31MR71E225KA93
C3: MURATA GRM32DR71E106KA12B
C4, C5: MURATA GRM21BR71H104KA01B
D1: ZETEX ZLLS2000TA
L1: TOKO B992AS-100M
LEDS: LUXEON III (WHITE)
M1: ZETEX ZXMP6A13GTA
Q1: PHILIPS PMBT3906
Q1
PWM
5V/DIV
I
LED
1A/DIV
I
L1
1A/DIV
2µs/DIVPV
IN
= 32V
f
OSC
= 1.2MHz
I
LED
= 1A
3518 TA05b
PWM DUTY CYCLE (%)
0
40
EFFICIENCY (%)
50
60
70
80
90
100
20 40 60 80
3518 TA05c
100
CTRL = V
REF